Combined arc lamp and incandescent lamp



March 7, 1939. I BRUNK 2,149,505

COMBINED ARC LAMP AND INGANDESCEN'ZI. LAMP Filed Ma 21, 1957 2 Sheets-Sheet 1 X} 111 v dfbvog w March 7, 1939. H. BRUNK COMBINED ARC LAMP AND INCANDESCENT LAMP 2 Sheets-Sheet 2 Filed May 21, 1937 Patented Mar. 7, 1939 UNITED STATES PATENT OFFICE COMBINED ARC LAMP AND INCANDESCENT LAW Harold J. Brunk, Chicago, Ill., assignor to The O. F. Pease Company, a corporation of Delaware Application May 21, 1937, Serial No. 144,090

1 Claim. (01. 1769) This invention relates to improvements in comlight, which latter is the desired output in the bined arc lamps and incandescent lamps, and case of a lamp.

while such equipment is adapted for many pur- The present invention comprises means for poses it is particularly useful as a source of light greatly increasing the light output of such dein blue print machines and the like. vices; first, by providing a shunt path permitting 5 The main object of this invention is to provide a higher current concentration through the carequipment converting a much larger proportion bons without upsetting the adjustment of the soleof the energy into usable light than has heretonoid; and second, by replacing ballast resistances fore been possible with arc lamps. in the device by additional light sources or lamps The solenoid type of operating mechanism is having an equivalent resistance, the auxiliary 10 preferred in arc lamps of the automatic type, lamps not being rendered operative until the carwherein the separation of the carbons from each bons have assumed proper operating separation.

other is properly adjusted by the pull of the sole- Other features and advantages of this invention noid, which is in turn a function of the current will be apparent from the following specification l5 flow across the carbons. When the carbons are and the drawings, in which: separated too far, the resistance of the arc gap Figure l is a side elevation of a solenoidincreases, the current flow across the gap deoperated arc lamp; Figure 2 is a circuit diagram creases, and thus the solenoid pull is lessened and f such a lamp; Figure 3 is a circuit diagram of permits the carbons to move relatively closer toa lamp wh rein an ballast resistances are regether until the increasing current flow stops such placed by auxiliary lamps when the carbons have 20 movement. reached proper operating separation; Figure 4 For many reasons it has been found undesirable is a diagram of a circuit enabling ready adj 1; to pa m r an eight r n p r hr ment of the amount of current flow across the the solenoid of the aver e p O this yp and carbons; and Figure 5 is a diagram illustrating :13 in order to increase the amount of light radiated the alternate arrangement of lamps. by the a it is necessary to p Current through In the particular embodiment of the invention the carbons by some second or additional circuit illustrated in Figs. 1 and 2, a pair of carbons Which does not include the solenoid. My joint in nd II, movable with respect to each other,

Patent 1,992,650, issued February 26, 1935, shows are operatively carried in a lamp having a globe 3:) a method of increasing the cur e t through the I2 and a reflector I3. The upper carbon in is carbons without changin t e Current through the here shown as movable, its separation from the solenoid, by establishing a second or shunt circuit other carbon being determined by the position around the solenoid after the carbons have sepaof t movable rocker arm 14 movement f this rated and assumed p ope Operating position arm being effected, through appropriate linkage :as This enables the current density acros the gap, by movement of the core or plunger l5 as a result and thus the light intensity, to be varied through of current flowing i th solenoid "5 A dasha Wide range, W e t are p maintains great pot I! is provided to prevent sudden movement of stability. the carbons and stabilize the lamp.

Such a secondary circuit, however, must absorb The rocker arm is here shown as carrying a a voltage drop equal to that across the solenoid. mercury switch I8. Reference more particularly 4() That is, should the carbons and the solenoid be in to Figure 2 will show that this mercury switch is series across a 220 volt supply line, either A. 0. connected in circuit between the carbons and an or D. C., and each have a 110 volt drop thereincandescent lamp 19. The solenoid I6 has in across. it is necessa y t the S ond 0 Shunt series therewith an adjustable resistance 20.

circuit include a ballast resistance of some type Thus, two current paths are provided through 5 substantially equivalent to the arc gap resistance the carbons: one, a series circuit including the in order to absorb the extra 110 Volt drOI Whe carbons, the solenoid, and the resistance 20; and it s placed in series with the carbons across the the other a second series circuit including the supply line. It is alw y n ry to use also a carbons, the mercury switch l8, and the incanballast resistance in series with the solenoid in descent lamp [9. It will be noted that the in- 50 order to achieve arc stability. candescent lamp is in shunt across the solenoid It has hereto ore bee us y to use imand the resistance 20, so that current flowing pedances of one type or another for such ballast through it flows directly through the carbons purposes, as shown in my prior patent. Such without any effect on the solenoid. 56 ballast resistances absorb power without giving off The mercury switch is so arranged that when the carbons are in contact with each other, the circuit therethrough is bro-ken, and the only current flow is through the solenoid and the resistance 20. Movement of the rocker arm I4, as the carbons separate, causes the mercury switch to tilt, however, and the apparatus is so constructed and arranged that when the carbons have reached proper operating separation the mercury switch closes the circuit through the incandescent lamp, thus materially increasing the flow of current through the carbons due to the provision of two circuits, and thus increasing also the amount of light given off thereby. Not only does this additional current result in a much higher proportion of light being given oh by the carbons, but the total light is increased by that given o-fi by the filament of the second or auxiliary lamp l9, which is mounted adjacent the arc lamp.

In many uses of the arc lamp, as for example by photoengravers, the amount of work done depends on the total candle power of the light source, and it is obvious that when one or more thousand watt incandescent lamps, burning at full brilliancy, are added to the are as a light source, the total foot candles of the device are greatly increased. While the light from a gas-filled tungsten lamp is not of the best frequency to make blueprints, the addition of the light has a marked value even in such work. The incandescent lamps used to replace the resistances in such blueprinting lamps should be maintained in the blueprinting machine between the arc lamps, where they will help to build up the weak printing area otherwise encountered therebetween. An additional factor is that with a fairly heavy current flowing through the are, there is a greater production of actinic rays which are found at that end of the spectrum which is the most efiective in photographic work. For other uses, the incandescent lamps can be mounted in a special compartment around the outside of the standard arc lamp reflectors. Where general illumination is required in a room where such are lamps are employed, the ceiling or other lamps can be wired in, to act as resistors in connection with the carbons, thus achieving the greatest possible amount of light energy from current being consumed.

It will be readily apparent that any type of lamp having a resistance drop therein could be used for the secondary or auxiliary lamps. Not only the usual gas-filled tungsten filament lamp, common on the market today, but also high pressure mercury are or any other types of lamps are adapted to be used in series with the electric are as here disclosed. The principal purpose is to have all of the current used go toward making light, rather than being dissipated in undesired heat energy, one portion of the current developing light in the arc across the carbons, and the other portion developing additional light, which may or may not be of the same wave length as that of the arc, in the secondary or auxiliary lamps.

Referring more particularly to Figure 3, a circuit is shown wherein two auxiliary lamps are employed. The lamp 3% may be of considerable power, such as one thousand watts, and is connected in series with the carbons 32 and 33 through a mercury switch 34. As described in connection with Figure 2, this mercury switch closes the circuit when the carbons 32 and 33 have separated to proper operating distance. In addition, a smaller lamp 35, as of 600 watts, is provided to replace the resistance 36 in series with the sole-- noid 31 when the arc has been properly drawn. In order to accomplish this, a second mercury switch 31 is also mounted so as to be tilted by some moving part actuated by the solenoid, and as in the case of the other mercury switch, it may be mounted on the rocker arm of the device. This second switch is so arranged that when the carbons are in contact, the circuit through the wires 38 and 39 is completed and that through 4 and 4| is broken. That is, when the carbons are in contact or the arc is just starting there will be no current fiow through either of the lamps, the current flow being solely through the solenoid 37, the wires 38 and 39 and the ballast resistance 36. As soon as the arc has been properly started, however, the circuit through the wires 38 and 39 will be broken and that through 60 and ll completed, so that all current flowing through. the solenoid will now flow through the lamp 35, rather than through the resistance 38, thus converting its energy into useful light. Simultaneously, the switch 34 will complete the circuit through the lamp 3|, thus providing a shunt circuit around the solenoid, increasing the total amount of current fiow through the arc.

In the particular embodiment of this invention illustrated in Figure 4, the are through a pair of carbons 5| and 52 is started, as heretofore described, by current flowing through a series circuit including them, the solenoid 53, and the resistance 54. As soon as the arc has been properly started the mercury switch 55 closes, to provide a shunt circuit around the solenoid and resistance 5 3, which shunt circuit includes in series with the carbons a plurality of auxiliary lamps 55, 51, 58 and 59, all of which lamps are wired in parallel. A series of manually operable snap switches 66, BI, 62 and 63 are provided to permit selective operation of one or more of the auxiliary lamps. That is, none of the lamps providing a shunt circuit for additional current flow through the carbons, can come into operation until the circuit is automatically closed by the mercury switch when the carbons have moved to proper operating separation; but once the circuit has been closed by the mercury switch, the manual operation of the snap switches enables the total current through the carbons to be readily adjusted and permits additional current to flow therethrough, not only providing more light as a result of radiations from the arc, but also as a result of radiations from the auxiliary lamps.

Figure 5 illustrates a bank of lamps such as would be used in a blueprint machine, i. e., there are the same number of incandescent lamps 9% or other auxiliary lamps as there are are lamps 65, and the two types of lamps are mounted alternately in a row.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. The device to be substituted for the resistance need not necessarily be a lamp but may comprise any other current consuming device or translating de vice, such, for example, as a motor, which may be used in any kind of service. In some arc lamps now on the market the carbons are pulled apart by a motor driven mechanism and where such are lamps are used, the resistance of the motor windings may be made use of as a substitute for the incandescent lamp or other auxiliary sources of light. Also, although the switch shown and described in several forms of the invention is preferably a mercury switch, any other suitable type of switch may be used. It may be actuated or controlled electrically or otherwise by the movement of one of the carbons or any of the other movable parts associated therewith. Various changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claim, in which it is my intention to claim all novelty inherent in my invention as broadly as permissible, in view of the prior art.

The embodiment of the invention shown in Fig. 3 of the drawings is claimed in a divisional application, Serial No. 249,796, filed January '7, 1939.

I claim:

Apparatus of the character described, including: an arc lamp comprising a pair of relatively movable carbons; a solenoid for causing said relative movement; a series circuit including said carbons and said solenoid; a plurality of filament lamps connected in parallel; independent manual switches whereby said filament lamps are selectively controlled; switch means operatively connected to said carbons and afiected by movement thereof, said switch being open when said carbons are in contact with each other and closed when said carbons are separated a proper operating distance; and a second series circuit including said carbons, said switch means, and said filament lamps, said second circuit being so arranged that said filament lamps are in shunt about said solenoid.

HAROLD J. BRUNK. 

